Unit 2 Flashcards
What are the cranial bones?
2 parietal bones 2 temporal bones 1 frontal bone 1 occipital bone 1 sphenoid bone 1 ethmoid bone
Where are the paranasal sinuses located?
Frontal bone
These bones form most of the superior and lateral walls?
Parietal bones
These bones form the inferolateral (inferior-lateral) walls of the cranium?
Temporal bones
The squamous suture is the meeting point of these two bones?
Temporal and parietal bones
The canal that leads to the eardrum and middle ear?
External acoustic meatus
Articulates with the mandible condyle to form the temporomandibular (TMJ)
Mandibular fossa
Projection that serves as a point of attachment for some neck muscles (such as the sternocleidomastoid muscle) and is filled with air cavities (sinuses) that can get infected by bacteria entered from the middle ear
Mastoid process
Zygomatic arch =
Zygomatic process of temporal bone + zygomatic bone
Opening in inferior part of the temporal bone that allows passage of artery to the brain?
Carotid canal
Opening in inferior part of temporal bone that allows passage of the internal vein from the brain?
Jugular foramen
Meets the parietal bones at the lambdoid suture?
Occipital bone
Opening in the base of the occipital bone where the lowest part of the brain (medulla oblongata) meets the spinal cord?
Foramen magnum
This joint articulates with C1/Atlas and allows for flexion and extension of the head when one indicates “yes”
Occipital condyles
This bone forms part of orbit of eye, some of the floor of the skull, and a little of the lateral portion of the skull?
Sphenoid bone
This is where the pituitary gland is located?
Hypophyseal fossa of Stella turcica
Allows passage of optic nerve from eye to brain?
Optic canal
Lateral aspects of sphenoid bone that forms a portion of the lateral surface of the skull and a portion of the floor of the cranium
Greater wings
This bone forms roof of nasal cavity and part of the nasal septum?
Ethmoid bone
Specific part that forms roof of nasal cavity?
Cribriform plates
Projections that serve as sites of attachment for muscles? (4 total)
Tuberosity
Trochanter
Tubercle
Epicondyle
Tiny holes in cribriform plate that allows passage of nerve fibers that convey signals for the sense of smell?
Olfactory foramina
Small projection that extends between the cribriform plate?
Crista galli
Forms the superior part of the nasal septum?
Perpendicular plate
Forms most of the upper jaw and most of the hard palate?
Maxillary bones (singular = maxilla)
Ridge that bears the upper teeth?
Alveolar margin or process
Forms the anterior part and most (3/4) of the hard palate?
Palatine processes
Forms the posterior part (small portion) of hard palate?
Palatine bone
Cleft palate results when these fail to fuse medially during fetal development?
Palatine bone and palatine processes
These bones form your cheek bones?
Zygomatic bones
These bones provide for the passage of tears from the orbit to the nasal cavity?
Lacrimal bones
These form the bridge of your nose?
Nasal bones
Forms the inferior portion of the nasal septum?
Vomer bone
The only moveable bone in the skull?
Mandible
Paired bones that project from inferior aspect of lateral walls of nasal cavity?
Inferior turbinates/conchae (concha = singular)
Articulates with mandibular fossa of temporal bone to form temporomandibular joint (TMJ)?
Mandibular condyle / head of mandible
Ridge that bears the lower teeth?
Alveolar margin
What are “Rami” (singular = Ramus)?
Vertical portions of mandible
The openings on medial aspect of mandible that allows passage of the inferior alveolar nerve (branch of trigeminal nerve) to the lower teeth?
Mandibular foramen
Opening that allows passage of a nerve to the chin?
Mental foramen
Roofing nasal cavity is formed by what?
Cribriform plates of ethmoid bone
The floor of the nasal cavity is formed by what?
Palatine processes of maxilla and palatine bone (hard palate)
Lateral walls of the nasal cavity are formed by what?
Nasal conchae/turbinates (superior, middle and inferior)
What forms the anterior wall of nasal cavity?
External nasal cartilage and the nasal bones
The superior part of nasal septum is formed by?
Perpendicular plate of ethmoid bone
What forms the inferior part of the nasal septum?
Vomer bone
Anterior part of nasal septum is formed by?
Septal cartilage
Air-filled spaces that surround the nasal cavity?
Paranasal sinuses
How many bones are in the orbits (eye sockets)?
Seven
The orbits/eye sockets are made up of these four components?
Eyeballs, fat, lacrimal (tear) glands, and small skeletal muscles
This bone is not part of skull, is located one inch above larynx, is the only bone in the body that does not directly articulate with another bone and is the attachment site for muscles associated with swallowing?
Hyoid bone
Soft spots in the fetal and infant skull?
Fontanelles
Advantages and disadvantages of fontanelles?
Advantages: allows brain growth and allows for compression of the skull during birth
Disadvantages: they don’t give as much protection as bone does
How many bones are in the vertebral column?
7 cervical vertebrae + 12 thoracic vertebrae + 5 lumbar vertebrae + 1 sacrum (5 fused vertebrae) + 1 coccyx (most often 4 fused vertebrae) = 26
The major supporting ligaments of the vertebral column / spinal column / spine?
Anterior and posterior longitudinal ligaments
Intervertebral discs consists of?
An outer fibrocartilage later (anulus fibrosus) and an inner gelatinous core (nucleus pulposus)
The orbits/eye sockets are made up of these four components?
Eyeballs, fat, lacrimal (tear) glands, and small skeletal muscles
This bone is not part of skull, is located one inch above larynx, is the only bone in the body that does not directly articulate with another bone and is the attachment site for muscles associated with swallowing?
Hyoid bone
Soft spots in the fetal and infant skull?
Fontanelles
Advantages and disadvantages of fontanelles?
Advantages: allows brain growth and allows for compression of the skull during birth
Disadvantages: they don’t give as much protection as bone does
How many bones are in the vertebral column?
7 cervical vertebrae + 12 thoracic vertebrae + 5 lumbar vertebrae + 1 sacrum (5 fused vertebrae) + 1 coccyx (most often 4 fused vertebrae) = 26
The major supporting ligaments of the vertebral column / spinal column / spine?
Anterior and posterior longitudinal ligaments
Abnormal lateral curvature of the thoracic vertebrae?
Scoliosis
Exaggerated posterior curvature of the thoracic vertebrae?
Kyphosis/hunchback (common in elderly women because of vertebrae fractures due to osteoporosis; aka dowagers hump)
Exaggerated anterior curvature of the lumbar vertebrae?
Lordosis/Swayback (common in obese men and pregnant women)
What is the anterior disc-shaped, weight-bearing portion of vertebra?
Body/Centrum
The posterior arch-shaped part of vertebra?
Vertebral arch
Posterior portions of the vertebral arch? (Spinal bifida is characterized by the failure of formation of these during fetal development)
Laminae (singular = lamina)
Surgical removal of lamina to relieve a herniated disc?
Laminectomy
The opening between the body/centrum and vetebral arch?
Vetebral foramen
The area in which the spinal cord passes?
Vertebral canal
Single projection that extends posteriorly from the vertebral arch? (The laminae lie at its base)
Spinous process
Two projections that extend laterally from the vertebral arch?
Transverse processes
The projections by which a given vertebra articulates with the vertebra above it and below it?
Superior and inferior articular processes
Holes between adjacent vertebrae through which the spinal nerve passes?
Intervertebral foramina
In the cervical vertebrae, this is where the vertebral arteries course in route to brain?
Transverse foramina
Articulates with the axis to form the alanto-axial joint (a pivot-type joint that allows you to rotate your head side to side to indicate “no”)?
Dens/odontoid process
The 7th cervical vertebra that can be seen or felt through the skin at the base of the posterior neck?
Vertebra prominens
The section of vertebrae responsible for supporting weight?
Lumbar vertebrae
The sacrum and ilium are connected by this joint?
Sacroiliac joint
What are the two parts of the vertebral column that can hinder delivery?
The sacral promontory of the sacrum and the coccyx
How many ribs are attached to the sternum via costal cartilage?
10
Medial end of clavicle articulates with this part of the sternum?
Manubrium
Largest part of the sternum?
The body
Inferior tip of sternum (hyaline cartilage until 40’s)?
Xiphoid process
Horizontal ridge on front of sternum where the Manubrium meets the body?
Sternal angle
True ribs?
Pairs 1-7
False ribs?
Pairs 8-12
Spaces between the ribs that are filled with breathing-related skeletal muscle?
Intercostal spaces
Muscles associated with inhalation/inspiration?
External intercostal muscles
What muscles are associated with exhalation/expiration?
Internal intercostal muscles
What bone attached to the axial skeleton to allows the scapula to move freely?
Clavicle
The socket of the shoulder joint that is shallow and vulnerable to dislocation?
Scapulas glenoid cavity
If the clavicle is broken, which way would your shoulder cave?
Cave in medially
Projection on scapula that forms the tip of shoulder?
Acromion
Ridge on posterior scapula?
Spine
Skeletal muscle located above the spine of scapula?
Supraspinatus
Skeletal muscle located below the spine of scapula?
Infraspinatus
Shallow concavities above and below the scapular spine?
Supraspinatus and infraspinatus fossae
Projection that attaches to the tendon of the biceps brachii?
Coracoid process
(Medial or lateral)
Vertebral border?
Axillary border?
Vertebral = medial
Axillary = lateral
Proximal end of humerus, articulates with the glenoid cavity?
Head of humerus
Part of humerus bone prone to fracturing?
Surgical neck
Projections on proximal humerus where the rotator cuff muscle insert?
Greater and lesser tubercles
Bump on shaft of humerus where the deltoid muscle inserts?
Deltoid tuberosity
Spool-shaped process on distal humerus that fits into the trochlear notch of the ulna?
Trochlea
Projection adjacent to trochlea on distal aspect of humerus?
Capitulum
Concavity in the distal humerus where the olecranon process of the ulna fits when the arm is fully extended?
Olecranon fossa
Projections on distal humerus where some muscles of the forearm attach?
Medial and lateral epicondyles
This bone is separated from the carpal bones by a disc of fibrocartilage and has very little involvement with wrist movements?
The ulna
(Medial or lateral)
Ulna?
Radius?
Ulna = medial (pinky side)
Radius = lateral (thumb side)
The bump where the tendon of the biceps brachii muscle inserts?
Radial Tuberosity
The radial artery passes over this bone?
Styloid process
Proximal radioulnar joint?
Radial notch and head of radius
During this type of movement, part of the radius crosses over part of the ulna making the two bones form an “X”?
Pronation
The two carpal bones that directly articulate with the distal end of the radius?
Scaphoid and lunate
Ulna contributes to the ____ joint?
Radius contributes to the ____ joint?
Ulna = elbow
Radius = wrist
A fracture in the distal radius resulting from falling with outstretched arms?
A Colleś fracture
Most frequently fractured wrist bone?
Scaphoid
The wrist is more concave on its ____ side?
Anterior
What forms the carpal tunnel?
Transverse carpal ligament/flexor retinaculum
Carpal tunnel syndrome is when?
Inflammation and swellings of tendons in the carpal tunnel lead to compression of the median nerve
The three major portions of the coxal/hip bone?
Ilium, pubis, ischium
- largest portion of hip bone
- has the iliac crest
- articulates with the sacrum to form the sacroiliac joint
- has the iliac fossa
- has the greater sciatic notch
Ilium
Anterior, inferior portion of hip bone?
Pubis
The pubis of one hip bone articulates with the pubis of the other hip bone to form a ____ joint called the _____?
Cartilaginous-type joint, pubic symphysis
Posteroinferior (posterior, inferior) portion of hip bone?
Ischium
Big bump that bears your weight when you are sitting and is the attachment site for hamstring muscles?
Ischial tuberosity
Sharp point that angles into the pelvic outlet and can hinder delivery?
Ischial spine
Deep socket in each hip bone where the ilium, pubis, and ischium meet, and where the head of the femur meets to form the hip joint?
Acetabulum
Very large opening in the hip/coxal bone?
Obturator foramen
The bony pelvis consists of?
2 hip bones + sacrum + coccyx
The portion of the bony pelvis that is located superior to the pelvic brim and medial to the flared portions of of the two ilia of the hip bones?
False/greater pelvis
Portion of bony pelvis located inferior to the pelvic brim?
True/lesser pelvis
The female pelvis is adapted for childbearing; it is wider, shallower and lighter than that of a male. This provides for more room in the ____?
True/lesser pelvis
The superior opening in the true pelvis?
Pelvic outlet
The inferior opening out of the true pelvis?
Pelvic outlet
Bony protrusions that can hinder delivery?
The sacral promontory, the coccyx, and the Ischial spines
Largest bone in body also not in the anatomical leg?
Femur
Weakest part of the femur and is what actually breaks in a “broken hip”? (Susceptible to growing weaker in post-menopausal women with osteoporosis)
Neck of femur
Projections on proximal femur to which muscles attach?
Greater and lesser trochanters
Projection on posterior aspect of femur shaft where the gluteus maximus muscle attaches?
Gluteal tuberosity
This bone is enclosed in the quadriceps femoris tendon?
Patella (kneecap)
The more medial and larger of the two bones of the anatomical leg; helps form both knee and ankle joints?
Tibia
Sharp ridge on front of tibia that can be palpated (felt through the skin); the tibialis anterior muscle is immediately lateral to it?
Anterior/tibial crest
Bump on distal tibia that forms the inner (medial) bulge of the ankle area?
Medial malleolus
Thinner and more lateral of the two leg bones; does not bear weight, does not contribute to the ankle joint or the knee joint, articulates with the talus and provides some stability to the knee joint?
Fibula
Distal end of fibula; forms outer (lateral) bulge of the ankle area?
Lateral malleolus
You have ___ carpals and ___ tarsals?
8 carpals and 7 tarsals
Deformity of the hallux? (caused by tight fitting shoes)
Bunion
The arches of feet provide the foot with?
Springiness (resilience)
Arches of feet are maintained by?
- interlocking shape of foot bones
- ligaments that bond the bones of feet
- tendons of muscles that attach to those bones
A junction of two or more bones?
Joint/articulation
Diarthroses joints?
Freely moveable joints (predominate in the limbs)
Is based on the amount of movement allowed at a joint?
Functional classification
Structural classification is based on?
- The kind of connective tissue component that binds the articulating bones together
- the presence or absence of a joint cavity between the articulating bones
The three major (general) structural classes of joints?
Fibrous, cartilaginous, and synovial
_____ joint?
- tightly joined by fibrous connective tissue (consist largely of collagen fibers)
- no joint cavity present
- some are immovable
Example: sutures of skull
Fibrous joints
_____ joint?
- bones are joined by cartilage
- no joint cavity
- some are slightly moveable
Example: intervertebral joints (discs), public symphysis of pelvic girdle (connected by fibrocartilage)
Cartilaginous joints
____ joints?
- bones are joined by a synovial membrane and a fibrous capsule
- joint cavity is present
- are freely moveable joints (diarthroses joints)
Example: shoulder joint, elbow joint, wrist joint, hip joint, knee joint, ankle joint
Synovial joints
Two-layered sleeve that encloses joint cavity?
Articular/joint capsule
Outer layer and inner layer of articular/joint capsule?
(Synovial joint)
Outer layer = fibrous layer
Inner layer = synovial membrane
Slippery lubricating fluid released by the synovial membrane that helps nourish the articular cartilage?
(Synovial joints)
Synovial fluid
Layer of hyaline cartilage that covers the articulating surfaces on the bones in a synovial joint; reduces friction in a synovial joint and absorbs shock?
Articular cartilage
Ligaments that strengthen the fibrous capsule?
Reinforcing ligaments
Synovial joints
Vascular or avascular?
Vascular
In synovial joints these detect pain, but mainly monitor how much the capsule is being stretched (this monitoring is one of the ways the nervous system senses our posture and movements)?
Sensory nerve fibers
Flat, synovial fluid-filled sacs lines with a synovial membrane that reduce friction between joint-related structures that run against one another during movements?
Bursae (singular = bursa)
Pads of fibrocartilage that improve the fit between bones in certain synovial joints (knee joint and temporomandibular joint)?
Menisci/ articular discs
The shapes of articular surfaces of bones are important in regard to determining what?
The kinds of movement that are possible at a synovial joint
____ and _____ of synovial joints help hold the bones together and help prevent excessive or undesirable motions?
Ligaments and joint/articular capsule
The tension in a skeletal muscle when it is partially contracted, yet is not causing movement; helps stabilize joints and keep the bones in the proper position
Muscle tone
Muscle tone is especially important relative to the reinforcement of _____, ______, and ______?
Shoulder joint, knee joint and arches of the foot
Decreases the angle between the bones of a joint and brings the closer together
Examples: bending the forearm at the elbow, bending the leg at the knee, tilting head towards chest
Flexion
Increases the angle and distance between bones
Example: straightening the leg at the knee back from flexed position
Extension
Extension beyond the anatomical position; cannot happen to the knee or the elbow without causing injury?
Hyperextension
Movement of a limb away from the midline of the body?
Abduction
Movement of a limb toward the midline of the body?
Adduction
Semicircular movement of a bone; occurs at these three joints?
Rotation; shoulder joint, hip joint and atlanto-axial joint)
Occurs when the radius rotates around the ulna, crossing over the ulna to form an “X” in the forearm?
Pronation
Occurs when the radius rotates around the ulna to bring these bones into a parallel position relative to one another?
Supination
Turning the sole of the foot medially?
Inversion
Turning the sole of the foot laterally?
Eversion
Movement at the ankle that moves the instep (top) of the foot up and towards the shin?
Dorsiflexion
Movement at the ankle that moves the foot downward (occurs when you stand on your toes)?
Plantar flexion
Non-angular movement in which a bone is moved straight forward?
Example: drawing the shoulders forward
Protraction
Non-angular movement in which a bone is moved straight back?
Example: “squaring” the shoulders
Retraction
Non-angular movement in which a bone is moved straight up?
Example: shrugging the shoulders
Elevation
Non-angular movement in which a bone is moved straight down?
Example: dropping the shoulders
Depression
The primary factor that determines the movements at a synovial joint?
The shapes of the articulating bone surfaces (determined how the bones fit together)
Specific type of synovial joint allows for flexion and extension
Example: elbow joint, knee joint and the atlanto-occipital joint
Hinge joint
Specific type of synovial joint that allows for rotation
Example: atlanto-axial joint (joint between atlas and the axis dens/odontoid process) and the proximal radio-ulnar joint (pronation and supination)
Pivot joint
Specific type of synovial joint that allows for a wide variety of movements
Example: shoulder and hip joint
Ball-and-socket joint
The most commonly dislocated joint in the body?
Temporomandibular joint (TMJ)
Temporomandibular joint consists of these components?
Head/mandibular condyle of the mandible and the mandibular fossa of the temporal bone
The shoulder joint consists of these components?
Head of humerus and the glenoid cavity of the scapula
The most freely moving joint in the body?
Shoulder joint
The four specific skeletal muscles in the rotator cuff?
Supraspinatus, infraspinatus, subscapularis and teres minor
Elbow joint consists of?
Trochlea of the humerus into the trochlear notch of the ulna
Involves the articulation of the radius with the scaphoid and lunate bones?
Wrist joint
What forms the hip joint?
the articulation of the head of the femur with the acetabulum of the hip/coxal bone
The largest and most complex joint in the body?
Knee joint
The knee joint consists of?
The junction of the wheel-shaped condyles of the femur with the flat condyles of the tibia
This tendon encloses the patella at the anterior aspect of the knee joint?
The tendon of quadriceps femoris muscle group
The ligament that descends from the patella to insert on the tibial tuberosity?
Patellar ligament
Bursa located immediately beneath the skin and in front of the patella?
Subcutaneous prepatellar bursa
Common result of hard bumps to the kneecap come from? (Water on the knee)
Inflammation of the subcutaneous prepatellar bursa
The main stabilizing factor for the knee joint?
Muscle tone/tension in the skeletal muscles and tendons that surround it
Sprain is in a ______?
Strain is in a _______?
Sprain = ligament
Strain = muscle
The extracapsular ligaments includes the?
Collateral ligaments
Fibular/lateral collateral ligament (extends from the femurs lateral epicondyle to the fibula)
Tibial/medial collateral ligament (extends from the femurs medial epicondyle to the tibia)
The intracapsular ligaments include?
Anterior and posterior cruciate ligaments (cross over one another in knee joint; each cruciate ligament extends from the distal femur to the proximal tibia)
One of the main reasons why the knee joint is not very stable and is prone to injury?
The flat tibial condyles do not provide a secure socket for the femur condyles to fit into
Hard lateral horizontal blows tend to tear?
The tibial collateral ligament, medial meniscus, and anterior cruciate ligament
The most common injury to the anterior cruciate ligament is from?
The twisting of a hyperextended knee (ACL injury has very little healing capacity and has to be replaced)
Ankle joint consists of?
The articulation of the distal tibia and distal fibula with the talus
When bones of a joint are forced out of alignment?
Dislocation (higher risk of a repeat if already previously dislocated)
Torn cartilage injury of the knee involves?
Tearing of a meniscus in the knee joint
Outpatient procedure of knee joint surgery?
Arthroscopic surgery (can’t also be used for other joints, not just knee)
Inflammation of a bursa?
Bursitis
Olecranon bursitis?
“Students elbow” inflammation of the bursa located between the ulnas olecranon and the skin
Chronic forms of arthritis?
Rheumatoid arthritis and osteoarthritis
“Wear and tear” arthritis; involves the degeneration of articular cartilage; part of the aging process in humans
Osteoarthritis
An autoimmune disease; involves inflammation and degeneration of the synovial membranes followed by the formation of scar tissue and ossification (scar tissue fuses together bones)?
Rheumatoid arthritis
Muscle cells are called?
Muscle fibers (because of their thread like shape)
All muscles fibers (cells) contain the protein myofilaments?
Actin and myosin
The prefixes “myo” and “sarco” pertains to?
Muscle
Sarcoplasm =
Sarcolemma =
Sarcoplasm = cytoplasm of a muscle cell (fiber)
Sarcolemma = the plasma membrane of a muscle cell (fiber)
The cellular organelles in muscle cell (fiber) that produce the most ATP?
Mitochondria
Muscle tissues have ____ blood supply?
Good (are well vascularized)
Even though skeletal muscle are often attached to bones via tendons, facial muscles attach to?
The skin
It’s cells are multinucleated and striated?
Skeletal muscle tissue
A voluntary muscle controlled by the somatic motor nervous system; contains myofibrils, sarcomeres, and sarcoplasmic reticulum?
Skeletal muscle tissue
A thick layer of cardiac muscle tissue (only found on the heart)?
Myocardium
It’s cells are striated and and arranged in branching chains?
Cardiac muscle tissue
The ends of cardiac muscle cells (fibers) are joined by _____ in which ____ are located?
Intercalated discs; gap junctions
The hearts natural pacemaker enables the heart to beat/contract without being stimulated by?
The nervous system
Can increase or decrease the heart rate to meet changing needs of body?
Autonomic nervous system
Located in the walls of hollow internal organs?
Smooth muscle tissue
Visceral muscle is another name for?
Smooth muscle
It’s cells have no striations?
Smooth muscle tissue
Wave-like contractions made from the smooth muscle to help push food down the digestive tract and urine through the ureters?
Peristalsis
Involuntary muscle that contracts under the autonomic nervous system?
Both cardiac muscle and smooth muscle
The functions of skeletal muscle?
- Produces movement (primarily moves bones but also moves skin for facial expressions)
- maintains posture (provided by muscle tone)
- stabilizes joints (provided by muscle tone)
- generates heat (skeletal muscle contractions produce heat to maintain body temp)
Sheath of connective tissue around an entire skeletal muscle (either in the form of a tendon or a broad sheet-like aponeurosis)?
Epimysium
Connective tissue wrapping around an entire bundle of skeletal muscle fibers/cells (a fascicle)?
Perimysium
Connective tissue around a single skeletal muscle/fiber?
Endomysium
Skeletal muscles extend from one bone to another crossing at least one ____?
Moveable joint
The attachment of a skeletal muscle that remains fixed/stationary/immobile when the muscle contracts?
Origin
The moveable attachment of a skeletal muscle?
Insertion
Skeletal muscle attaches to their origins and insertions via _____ or _____?
Tendons or aponeuroses
Most of them attach to bones but they also attach to skin in the face
It’s cells are elongated, striated and multinucleated?
Skeletal muscle tissue
Sarcolemma =
Sarcoplasm =
Sarcolemma = plasma membrane of muscle fibers/cells
Sarcoplasm = cytoplasm of muscle fibers/cells
The sarcoplasm contains many long rod(cylinder)-shaped organelles named?
Myofibrils
Myofibrils consist of subunits called _____; (the basic units of contraction in skeletal muscle)
Sarcomeres
Each sarcomere is composed of _____ and _____?
Thin/actin filaments and thick/myosin filaments
A sarcomere is the portion of a myofibril between two consecutive _____?
Z discs
The thick/myosin filaments bear tiny knobs called?
Cross bridges/myosin heads
The portion of the sarcomere where both the entire length of the thick filaments and the inner portions of the thin filaments are present?
A bands
When a sarcomere is relaxed, the H zones in the center of A bands contain only ____?
Thick/myosin filaments
The light bands on the outer portions of a sarcomere that contain only thin/actin filaments?
I bands
Specialized organelle in skeletal muscle cells whose terminal cisterns release calcium ions upon being stimulated? (They allow for contraction of skeletal muscle by allowing the interaction between the myosin heads and the actin via calcium ions)
Sarcoplasmic reticulum
Contraction of skeletal muscle is ultimately controlled by?
Nerve cells that generate impulses (signals)
What is the job of T tubules?
Send nerve impulses to the sarcoplasmic reticulum, releasing calcium ions to bind together the myosin/thick filaments and actin/thin filaments
When sarcomeres contract and shorten, the cells in which they are located do what?
Contract and shorten ( thick and thin filaments do not change in length, rather their position to one another change)
To contract, a skeletal muscle fiber/cell must be stimulated by a?
Motor neuron of the somatic motor nervous system
A motor unit consists of?
A single motor neuron plus all the muscle cells it is responsible for stimulating
There is always one motor neuron per motor unit but the number of skeletal muscle cells per motor unit varies from?
Less than ten to several hundred
The very precise control of some skeletal muscles (ones that move the fingers and eyes) involves motor units having ____ muscle cells per unit?
Very few
The activation of large and powerful muscles (thighs) involves motor units having ____ muscle cells per unit?
Many
What is it called when axon terminals form junctions with the sarcolemma of skeletal muscle cells?
Neuromuscular junctions (motor end plates)
Although the axon terminals and the sarcolemma get very close to one another, they never touch. This gap is called?
Synaptic cleft
When a nerve impulse reaches the axon terminals their synaptic vesicles release a neurotransmitter called ______ into the synaptic cleft?
Acetylcholine
An autoimmune disease characterized by the attack of ones own immune system against ones own acetylcholine receptors of skeletal muscle cells?
Myasthenia gravis (loss of acetylcholine receptors = loss of normal stimulation of skeletal muscle)
A group of inherited diseases characterized by degeneration of skeletal muscle cells/fibers and weakening of entire skeletal muscle?
Muscular dystrophy (most common involves absence of a particular protein)
The different types of skeletal muscle cells?
- slow oxidative fibers
- fast glycolytic fibers
- fast oxidative fibers
These contract slowly, produce ATP, contain a LARGE number of mitochondria, have a richer supply of capillaries, are very resistant to fatigue, are thin in diameter, are red due to abundant myoglobin, and do not generate much contraction power?
Slow oxidative fibers (red slow twitch fibers)
*Responsible for maintaining posture for long periods of time
These contract quickly, produce ATP via glycolysis, pale in color from little myoglobin, have fewer mitochondria, supplied with fewer capillaries, less resistant to fatigue, contagion more actin, myosin and myofibrils, have a larger diameter, and generate powerful contractions?
Fast glycolytic fibers (white fast twitch fibers)
*in arm muscles and are capable of lifting heavy objects for brief periods of time)
_____ fibers are present in calf muscles and help propel the body in a short sprint?
______ fibers are used in long distance running?
______ fibers are used to maintain a standing posture for hours?
Fast glycolytic fibers
Fast oxidative fibers
Slow oxidative fibers
Although everyone has the mixture of the 3 types of skeletal muscle fibers, some people can have?
More of one type over another (genetically determined)
Increases the diameter and strength of fast glycolytic fibers because it stimulates the production of contractile proteins (actin and myosin) and myofibrils?
Weight lifting (resistance/strength training)
A muscle that’s largely responsible for causing a given movement?
Prime mover/agonist
Muscle that opposes or reverses a particular movement produced by a prime mover/agonist?
Antagonist
Help prime movers by producing the same movement or by reducing undesirable movements when a prime mover contracts?
Synergists
Muscles that move portions of the limbs are located ______ to the relatively distal parts they move?
Proximally
What is Bell’s palsy?
Paralysis of facial muscles associated with dysfunction of the facial nerve
The two-part muscle consisting of a frontal belly and an occipital belly connected by aponeurosis?
Epicranius
Muscle that surrounds anterior aspect of the eye?
Orbicularis oculi
Muscle that encircles and forms core if lips?
Orbicularis oris
Muscle that draws corners of mouth up (called the “smiling muscle”)?
Zygomaticus (major and minor)
Cheek muscle; compresses cheeks in ways that make blowing whistling, and sucking possible; holds food between teeth during chewing; well developed in infants?
Buccinator
Superficial, anterior neck muscle; tenses skin in anterior neck; pulls mandible and skin at edge of mouth downward?
Platysma
How many muscles are used to move an eyeball?
Six
The tough white outer cost of the eyeball?
Sclera
Muscle that moves the eyeball upward?
Superior rectus
Muscle that moves eyeball downward?
Inferior rectus
Muscle that moves eyeball medially?
Medial rectus
Muscle that moves eyeball laterally?
Lateral rectus
Muscles that helps rotate eyeball?
Superior oblique; inferior oblique
Muscles that move mandible; provides for mastication/chewing and biting?
Masseter and temporalis
Muscle that can be felt through skin when teeth are clenched; covers lateral aspect of mandibular ramus?
Masseter
Covers part of temporal and parietal bones; bulging of it can be felt through scalp when teeth are clenched?
Temporalis
Swallowing begins when the _______ and ______ muscles squeeze food posteriorly through the mouth towards the pharynx?
Tongue and buccinator
Located above the hyoid bone, this muscle helps pull the hyoid and larynx superiorly and anteriorly. This moves the laryngeal opening under the epiglottis (flap that keeps food and fluid out of the respiratory tract). Anterior movement of the hyoid bone widens the pharynx to better receive food?
Suprahyoid muscles
These muscles are next in line after the suprahyroid muscles; in the wall of the pharynx; squeezes food inferiorly through the pharynx and into the esophagus?
Pharyngeal constrictor muscles
Located below the hyoid bone, this muscle pulls the hyoid and larynx inferiorly to their resting positions as swallowing ends?
Infrahyoid muscles
Anterolateral surface of neck; origin: sternum and clavicle; insertion: mastoid process; flexes head and neck; rotates and tilts head; spasms of this muscle cause torticollis/wry (when the neck stays twisted to one side)?
Sternocleidomastoid
The two muscles in posterior neck; lie deep to trapezius; insertion: occipital bone; they extend and hyperextend head?
Splenius muscles
Group of muscles located in the deep back on both sides of the vertebral column; causes extension of spine, provides for erect posture, and help bend the spine laterally? ( after back surgery, this muscle goes into painful spasms)
Erector spinae/ sarcospinalis (lifting a heavy load from a bent over position causes damage to this muscle)
The anterior and lateral abdominal wall contains fascia and these four pairs of thin sheet-like muscles?
- rectus abdominis
- external oblique
- internal oblique
- transverse abdominis
An abnormal protrusion of an abdominal component (portion of an internal organ) out of the abdominal cavity through a weak point in skeletal muscle?
Hernia
Involves the protrusion of a small portion of the small intestine or greater omentum through the inguinal canal?
Inguinal hernia
Involves the protrusion of a small portion of the small intestine or greater omentum through the middle of the rectus abdominis?
Umbilical hernia
Involves the protrusion of a small part of the upper stomach through an opening in the diaphragm (esophageal hiatus); only hernia that can be felt through the skin?
Hiatal hernia
Muscle that runs vertically along the anterior abdomen?
Rectus abdominis
Most superficial of the three muscles in the anterolateral abdominal wall; helps rotate and laterally bend trunk?
External oblique
Anterolateral abdominal wall between external oblique and transverse abdominis; helps rotate and laterally bend trunk?
Internal oblique
Deepest of the three anterolateral abdominal muscles?
Transverse abdominis
Forms the floor of the thoracic cavity; when relaxed is dome shaped but is flattened when contracting; PRIMARY muscle that provides for inspiration/inhalation?
Diaphragm (innervation: phrenic nerve)
Located between ribs; responsible for inspiration (inhalation)?
External intercostals
Located between ribs; responsible for expiration (exhalation)?
Internal intercostals
Muscles in the pelvic floor that support pelvic organs (uterus and urinary bladder)?
Pelvic diaphragm and urogenital diaphragm
Protracts the shoulder; lies deep to the pectoralis major?
Pectoralis minor
Also known as “boxers muscle”; lies deep and inferior to pectoral muscles on lateral aspect of rib cage; runs from lateral chest towards shoulder?
Serratus anterior
Large superficial muscle in the upper and middle back; elevates, depresses, and retracts shoulder; upper fibers run inferiorly, middle fibers run horizontally and lower fibers run superiorly towards the scapula?
Trapezius
Two rectangular muscles lying deep to trapezius; retract scapula “squaring shoulders”?
Rhomboids (major and minor)
Large superficial muscle of chest; flexes and adducts arm; pulls arm across chest?
Pectoralis major (insertion: humerus)
Broad, flat, superficial muscle that extends from lower back to upper arm; extends and adducts arm (draws arm backward and downward)?
Latissimus dorsi
Forms much of the fleshy portion of the shoulder area; common site for intramuscular injections; abducts arm (main abductor)?
Deltoid
Rotator cuff muscles consist of these four different specific muscles?
Supraspinatus, Infraspinatus, Teres minor, Subscapularis
What strengthens and stabilizes the shoulder joint?
The rotator cuff muscles and their tendons
The specific rotator cuff muscle that is the common site of injury for baseball players?
Supraspinatus
Lies superior to the scapular spine on the posterior scapula; helps to stabilize shoulder joint?
Supraspinatus
Lies inferior to the scapular spine on posterior scapula; stabilizes shoulder joint?
Infraspinatus
Small muscle inferior to infraspinatus; stabilizes shoulder joint?
Teres minor
Muscle that lies against anterior aspect of scapula; stabilizes shoulder joint?
Subscapularis
The muscles in the arm are separated into anterior and posterior compartments. The muscles in the anterior compartment are _____ of the forearm and the muscles in the posterior compartment _______ the forearm?
Flexors; extends
Two headed (two part) superficial muscle in anterior arm; flexes forearm?
Biceps brachii
Origin: coracoid process
Insertion: radial tuberosity
Lies deep to biceps brachii; flexes forearm; synergist of biceps brachii?
Brachialis
Three headed (three part) muscle in posterior arm; extends forearm?
Triceps brachii
Insertion: olecranon process of ulna
Superficial, lateral forearm muscle; forms lateral border of cubical fossa; flexes forearm; synergist of biceps brachii and brachialis?
Brachioradialis
Muscle in deep forearm; performs supination (turns forearm and palm forward or upward); inserts in radius?
Supinator
Muscle in anterior forearm; performs pronation (turns forearm and palm backward or downward)?
Pronator teres
At the wrist, tendons are held in place by bands of fascia (connective tissue) called ______?
Retinacula (singular= retinaculum)
There is a retinaculum on the front of the wrist called ______ and a retinaculum on the back of the wrist called ________?
Anterior flexor retinaculum/ transverse carpal ligament
Posterior extensor retinaculum
Carpal tunnel syndrome is associated with inflammation and pain in the area of the _______ and compression on the _______?
Anterior flexor retinaculum/ transverse carpal ligament
Median nerve
Flexors of the wrist and fingers:
- are located in the ______ compartment of the forearm
- are mainly supplied by the _____ nerve
- include these muscles
Anterior
Median
Flexor carpi radialis, palmaris longus, flexor carpi ulnaris
Extensors of the wrist and fingers:
- are located in the _____ compartment of the forearm
- are innervated by the ______ nerve
- include these specific muscles
Posterior
Radial
Extensor carpi radialis, extensor digitorum, extensor carpi ulnaris
(Tennis elbow is a soreness caused by overuse of tendons of the extensors in wrist)
A composite of two muscles, the iliacus and psoas major; extend from the vertebral column and ilium to anterior thigh?
Iliopsoas
Iliacus
a. Origin: _______
b. Insertion: _______
c. Action: ________
Ilium of hip bone
Femur
Flexion of thigh
Psoas major
a. Origin: _______
b. Insertion: _______
c. Action: ________
Lumbar vertebrae
Femur
Flexion of thigh
“Cut of meat”: tenderloin
Strap-like superficial muscle that runs obliquely across anterior surface of thigh to knee; helps produce the “cross-legged” position?
Sartorius
The quadriceps femoris muscle group consists of these four muscles:
Rectus femoris, vastus lateralis, vastus medialis, vastus intermedius
